ROAD-detection-based index similarity sorting filtering method

Abstract

The invention discloses a ROAD-detection-based index similarity sorting filtering method which comprises the following steps: calculating statistical volume of the sum of first k pixels having a minimal difference value with a central pixel; comparing a ROAD value corresponding to each pixel with a threshold value T; if the ROAD value of the pixel is greater than the T, confirming the pixel as pulse noise; performing pulse noise removing treatment on the basis of index similarity sorting; and defining a similarity function and confirming the pixel with the maximum similarity with surrounding pixels as an output of a window. Compared with the prior art, the method has the advantages that the useful edge information and pulse noise can be efficiently identified, and meanwhile, the pulse noise having a small difference with the surrounding pixels can be detected; when the similarity of a certain pixel is evaluated, a quantity value difference and a direction difference between the pixels are simultaneously used as an evidence for evaluating the similarity of the pixels; the effect of noise removing capacity is excellent; the color information of an image before and after being filtered is maintained; and the distortion and the loss of details and colors are avoided.

Description

technical field The invention relates to the technical field of image processing, in particular to a novel impulse noise filtering method for color images. Background technique Color image noise is regarded as a three-dimensional fluctuation vector in RGB space, which affects the distribution of real color vectors in the image. During the acquisition and transmission of color images, due to human factors (such as industrial machines, power switches, and various automotive devices located near the image transmission system) and natural factors (such as lightning, avalanches, etc.), the image may be affected by impulse noise. pollute. Impulse noise in grayscale images can be modeled with impulse distribution. Color images lack an effective multidimensional impulse noise model. There are some commonly used simplified noise models to analyze the performance and performance of different color image filters. The impulse noise model of the three-dimensional variable in the pri...

AI Technical Summary

Problems solved by technology

Among them, the vector median filter is one of the commonly used and effective nonlinear filters. However, since this filter performs median filtering on each pixel of the color image without distinction, high-frequency information such as details and edges It is mistakenly regarded as impulse noise and removed, resulting in serious loss of image information